Search results
Results from the WOW.Com Content Network
A hindlimb or back limb is one of the paired articulated appendages attached on the caudal end of a terrestrial tetrapod vertebrate's torso. [1] With reference to quadrupeds, the term hindleg or back leg is often used instead. In bipedal animals with an upright posture (e.g. humans and some primates), the term lower limb is often used.
For example, the radius and ulna of the forelimb, and the tibia and fibula of the hindlimb of the zeugopod are distinct from one another, as are the different fingers or toes in the autopod. These differences can be treated schematically by considering how they are reflected in each of the limb's three main axes.
Though in chicks, they seem to be the primary factors involved in limb identity, in mice it appears that Tbx4 is merely a downstream messenger enforcing the hindlimb-forming instructions of Pitx1. Whether Pitx1 merely diverts a prospective forelimb from that path to become a hindlimb, or if Tbx5 is activated by another Pitx1-like messenger, is ...
In the polyphyletic hypothesis (PH), frogs and salamanders evolved from dissorophoid temnospondyls while caecilians come out of microsaur lepospondyls, making both lepospondyls and temnospondyls true tetrapods.
Skeletons of a human and an elephant. Comparative foot morphology involves comparing the form of distal limb structures of a variety of terrestrial vertebrates.Understanding the role that the foot plays for each type of organism must take account of the differences in body type, foot shape, arrangement of structures, loading conditions and other variables.
The term "homology" was first used in biology by the anatomist Richard Owen in 1843 when studying the similarities of vertebrate fins and limbs, defining it as the "same organ in different animals under every variety of form and function", [6] and contrasting it with the matching term "analogy" which he used to describe different structures ...
In interferometric microscopy, the image of a micro-object is synthesized numerically as a coherent combination of partial images with registered amplitude and phase. [ 1 ] [ 2 ] For registration of partial images, a conventional holographic set-up is used with a reference wave, as is usual in optical holography .
Forelimbs in mammals have varying functions but are all homologous. A forelimb or front limb is one of the paired articulated appendages attached on the cranial end of a terrestrial tetrapod vertebrate's torso. With reference to quadrupeds, the term foreleg or front leg is often used instead.